Context Isolation
Prompt injection rides in retrieved content and tool output.
A quarantine bag for mail. You read it; you do not let it rewrite the law.
Visual Workflows
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Overview
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This turn
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A quarantine bag for mail. You read it; you do not let it rewrite the law.
Key Takeaways
- 1.Untrusted text must be fenced so it cannot override system rules.
- 2.Tool results, retrieved docs, and web pages are untrusted.
- 3.Use delimiters, roles, and treat that block as data not instructions.
- 4.Never concatenate untrusted text into the system prompt.
- 5.Prompt injection rides in retrieved content and tool output.
Learn elsewhere
- →Prompt Injection — Phase 20
Real Example
Scenario
Isolation: pack only what this turn needs.
What you would do
In Context Engineering, apply Context Isolation to this scenario: Isolation: pack only what this turn needs. Identify the inputs, run the technique, validate the output, and note one thing you would monitor in production.
Commands
Commands to Remember
Untrusted text must be fenced so it cannot override system rulesTool results, retrieved docs, and web pages are untrustedUse delimiters, roles, and treat that block as data not instructionsNever concatenate untrusted text into the system prompt
Cheat Sheet
Quick recap
quick ref- •Isolation
- •Budget
- •Don't dump
Common Mistakes
- ✕Skipping evaluation for Context Isolation before production
- ✕No logging or tracing around context isolation steps
- ✕Ignoring cost and latency implications